Interlocking block



FIG. 1 is a top, right side perspective view of an interlocking block, showing the design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a right side elevational view thereof, the side opposite being a mirror image;

FIG. 4 is a front elevational view thereof; and,

FIG. 5 is a rear elevational view thereof. 

The ornamental design for an interlocking block, as shown and described. 